A STUDY OF INELASTIC-COLLISIONS RB(7S)- THEORETICAL ASPECTS(RB(5S) )

The mechanisms of nonresonant excitation transfer process in thermal c ollisions of two rubidium atoms Rb(7S) + Rb(5S) --> Rb(5D) + Rb(5S) wa s studied theoretically, under conditions when the initial and final s tates of a system of two colliding atoms are not connected with each o ther by electric multipole transitions. Population processes of Rb 5D states were considered using calculated adiabatic potential curves of the Rb-2 quasimolecule in asymptotic approximation. The calculated cro ss-sections (sigma(theor) = 5.0 x 10(-15) cm(2)) are in good agreement with experimental results [sigma(exp) = (8.0 +/- 4.0) x 10(-15) cm(2) ] at thermal collision energies (T similar to 500 K).